Ovaries, Uterus, and Mammary Glands in Rabbit. 431 



alveoli and ducts were full of a milky secretion. Both ovaries contained 

 corpora lutea. There were no remains of tubes or uterus. 



(26) The uterus was removed from a virgin rabbit when 3 months old. 

 On the 27th day after copulation (which took place when maturity was 

 reached) fluid could be squeezed from the nipples. On the 28th day the 

 rabbit was killed, when it was found that the alveoli of the mammary glands 

 were well developed. The ovaries contained corpora lutea. There was 

 a small piece of one Fallopian tube left. 



(27) The uterus was removed from a virgin rabbit when 3 months old. 

 It reached maturity, copulated, as in the preceding cases, and was killed 

 17 days later. No remains of uterus or tubes could be found. The ovaries 

 contained eight (three and five) corpora lutea. The mammary glands were 

 well developed, the ducts and alveoli being filled with a secretion. 



These experiments show that mammary development occurring in rabbits 

 as a result of the formation of experimentally produced corpora lutea takes 

 place independently of any uterine influence. Thus the uterus is not 

 a factor in mammary growth any more than in ovarian growth. The 

 experiments show further that the presence of one ovary, with its contained 

 corpora lutea, is sufficient to bring about the mammary hypertrophy. 



The Influence of the Corpora Lutea upon the Uterus. 



It has been concluded by Fraenkel and others that the corpus luteum is 

 an essential factor in the fixation of the fertilised ovum to the uterine wall 

 and in the nourishment of the embryo during the first stages of pregnancy. 

 This conclusion is based on the results of ovariotomy during early pregnancy 

 and on a large number of control experiments. Whether or not the 

 evidence is sufficient to justify the theory being stated in precisely this 

 form, it would seem clear that the development of the corpus luteum is 

 functionally connected -with the contemporaneous hypertrophy of the uterine 

 wall during the first stages of gestation, since the raised nutrition of the 

 uterus is dependent upon the presence of the corpus luteum (Marshall and 

 Jolly). Ancel and Bouin state that in the case of the rabbit the non-pregnant 

 uterus undergoes hypertrophic changes when corpora lutea are developed. 

 This has been called in question by Dubreuil and Regaud, but Niskoubina's 

 observations are confirmatory of those of Ancel and Bouin. 



The following is an account of our observations upon the changes under- 

 gone by the non-pregnant uterus after ovulation consequent upon sterile 

 coition (excepting in the case of Experiment 11 where the rabbit had 

 ovulated spontaneously). The condition of the ovaries and mammary glands 

 has been already described. The numbers of the experiments provide a 



